Sea nettle (Chrysaora quinquecirrha) nematocyst venom is capable of injuring man and killing lower animals. Investigations on the pathophysiology of the neurotoxin and pain producing factors within this venom will be conducted. Efforts to purify these substances will be initiated. The role of allergy in injuring man will be defined by measuring the frequency of venom specific anti-IgE antibodies in susceptibles who have been stung. A higher degree of purification of the pain and lethal factors of the venom will be atempted through use of affinity chromatography. The progress of purification will be followed by analytical thin layer isoelectric focusing and disk gel electrophoresis. A rapid assay system for measuring the toxicologic actions of the venom will involve use of purified antibody. In order to determine whether the venom affects some postganglionic membranes the effect of the venom on a neuron which employs a non-acetylcholine transmitter (GABA) will be studied on a nerve-muscle preparation. The kinin-like and cardiac effects of isolated toxins will be investigated and compared with those found in other coelenterate venoms.